The approaches described in this section are approaches that could be pursued, but not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated, it should not be assumed that any of the approaches described in this section qualify as prior art merely by virtue of their inclusion in this section.
With the advent of the Internet and the World Wide Web (“Web”) a wide array of information is instantly accessible to individuals. However, because the Web is expanding at a rapid pace, the ability to find desired Web content is becoming increasingly difficult. Thus, search engines have been developed to assist individuals in finding the Web content they desire. Such search engines are normally accessible via search Web portals, such as the Yahoo! Inc. Web portal.
In order to search for Web content, users typically visit a web portal page. On a web portal page, users submit search queries as phrases representing the scope of the content they would like to view. Based on the search query, the web portal page invokes the search engine to find relevant Web pages containing the Web content and displays the results to the user.
A constant goal of search engines and Web portals is to ensure that the results shown to the user are relevant to the user's query. One approach for determining the relevancy of search results is by manually screening search results for each query. Typically, this requires that a developer or programmer run the search query on the search engine and manually check each of the results for relevance. The results are then ranked in terms of relevance and the most relevant results are displayed first to a user on a Web portal page. This approach, however, is very cumbersome and is prone to error. Further, because the Web is growing at a rapid pace, the amount of results that may potentially satisfy a search query heavily outweigh the manpower required to rank the relevance of each of the results.
Another approach is to track which results have been frequently “clicked” on by users of the Web portal. A Web portal user clicks on a result if the user wishes to visit or select the result for viewing. By clicking the result, the user is redirected from the Web portal to the desired Web page containing Web content. Web portals normally have a way of tracking the amount of clicks a particular result or link has received. Therefore, Web portals may determine which results are relevant by tracking which results have been clicked on the most by Web portal users. However, this approach is also prone to error. For example, although a user may have clicked on a result, it does not necessarily mean that the result is relevant. Specifically, search results displayed to a user are usually in the form of a title and an abstract. Many times, however, the title and abstract are not accurate indications of the actual content of a search result. Thus, although a user may have clicked on a particular result, the result may have no relevance to the search query.
Yet another drawback to the above approaches is the lack of variety checking. Although the relevance of search results is considered, there is no way for ensuring that an adequate variety of results are displayed to the user. For instance, some search queries may request Web content relating to a general topic. The general topic might contain many sub-topics that are also relevant to the search query. However, the above approaches do not attempt to ensure that enough results relating to sub-topics are displayed to the user when a query for the general topic is received.
Therefore, what is desired is an improved mechanism for automatically checking the relevance and variety of search results that does not suffer from the drawbacks of prior approaches.